The Preparation Of Paam/pva Hydrogel Interpenetrating Network And Cu Nanoparticle Assembly

Recent studies have shown that dispersing the inorganic nano-particles in the polymer hydrogel is not just the simple sum of the two performance, but in some ways to improve overall performance. Polymer Hydrogels which are crosslinked by chemical bond or physical force can form three-dimensional cross-linked polymer network. It can absorb dozens to thousands of the water compared to itself masses by continuous or discontinuous volume phase transition. Some hydrogel also has pH sensitivity and temperature sensitivity. Due to the unique physical and chemical nature, it is widely used in industry, agriculture, biology, materials and controlled release of drugs.After combined with two or more single component, the hydrogel-IPN hydrogel’s in-house special-IPN structure can enhance its mechanical strength and flexibility. When we improve the hydrogel performance, it usually causes the water gel system friable and poor mechanical strength during the application. This poor mechanical strength led to the difficulty to deal with. When we apply nano-particles dispersed IPN hydrogel to drug carriers and controlled-release system, it makes the overall Materials’ drugs loading quantity increase because of the increases of overall surface of material as well as the interaction between drugs. And by regulating the size of nanoparticles and polymer concentration, you can control the speed of drug releasing. Importantly, when we introduce the inorganic nano-particles, the material mechanical properties can also be improved to some extent, avoiding the difficulties of handle materials.In this study, the PVA/PAAm-IPN is prepared by chemical cross-linked synthesis, and sodium hypophosphite was used to generate copper nanoparticles as a reducing agent to reduce the copper (II). As a result, enhanced overall stress-strain behavior is acquired and expected to apply in drug controlled release system. The specific study includes:1) In the presence of glutaraldehyde and NNMBA, the PVA/PAAm interpenetrating network gels were synthesized. The formation of interpenetrating network gels improved the mechanical strength of gel, depending on the components of the PAAm and PVA and crosslinking agent proportion. Research found that swelling of the heterozygous gel is obviously faster than the rate of pure PAAm gel. Compression stress and strain experiments have found that the complexation between copper nanoparticles and interpenetrating networks gels plays an important role in improving the compressed mechanical performance.2) Well-dispersed copper nanoparticles were fabricated using poly(vinyl alcohol)/polyacrylamide interpenetrating polymer networks (PVA/PAAm IPNs) as a nanoreactor template. The synthesis of the IPNs hydrogels was achieved in the presence of glutaraldehyde and N,N’-methylene-bis-acrylamide. The resulting PVA/PAAm/Cu nanocomposite hydrogels were characterized, and the swelling and mechanical properties were investigated. The results indicated that the copper nanoparticles adopted a spherical shape with a size range from10to20nm. The complexation of PVA in PVA/PAAm IPNs with Cu2+plays an important role in avoiding the aggregation of copper nanoparticles and providing particle size and size distribution controllability and stability. Although the swelling capacity of the nanocomposite hydrogels was slightly lower than that of the control, they bore better compression mechanical properties. The water uptake and mechanical properties can be easily tuned by changing the component ratios to meet the requirements of the specific applications such as drug controlled release or tissue engineering.